From: Rusty Russell <rusty@rustcorp.com.au>
Date: Thu, 1 Dec 2011 06:15:51 +0000 (+1030)
Subject: ccanlint: get rid of separate class of compulsory tests.
X-Git-Url: https://git.ozlabs.org/?p=ccan;a=commitdiff_plain;h=60824f8a0f758dc7808eb31cc83434ea78f44ed1

ccanlint: get rid of separate class of compulsory tests.

It's reduced to a flag which means we stop processing the module.  We have
to enhance our dependencies a bit, but they've always been quite good.

This simplifies things quite a bit.
---

diff --git a/.gitignore b/.gitignore
index 6237a284..6b2b9fba 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,8 +9,7 @@ tools/doc_extract
 tools/namespacize
 tools/run_tests
 tools/ccanlint/ccanlint
-tools/ccanlint/generated-compulsory-tests
-tools/ccanlint/generated-normal-tests
+tools/ccanlint/generated-testlist
 inter-depends
 test-depends
 lib-depends
diff --git a/tools/ccanlint/Makefile b/tools/ccanlint/Makefile
index ee371e05..11d09e87 100644
--- a/tools/ccanlint/Makefile
+++ b/tools/ccanlint/Makefile
@@ -1,6 +1,5 @@
-COMPULSORY_TEST_CFILES := $(wildcard tools/ccanlint/compulsory_tests/*.c)
-NORMAL_TEST_CFILES := $(wildcard tools/ccanlint/tests/*.c)
-TEST_OBJS := $(NORMAL_TEST_CFILES:.c=.o) $(COMPULSORY_TEST_CFILES:.c=.o)
+TEST_CFILES := $(wildcard tools/ccanlint/tests/*.c)
+TEST_OBJS := $(TEST_CFILES:.c=.o)
 
 CORE_OBJS := \
 	ccan/asort/asort.o \
@@ -33,20 +32,16 @@ CORE_OBJS := \
 OBJS := $(CORE_OBJS) $(TEST_OBJS)
 
 # FIXME: write a trivial C program to do this
-tools/ccanlint/generated-normal-tests: $(NORMAL_TEST_CFILES)
-	cat $^ | grep ^REGISTER_TEST > $@
-tools/ccanlint/generated-compulsory-tests: $(COMPULSORY_TEST_CFILES)
+tools/ccanlint/generated-testlist: $(TEST_CFILES)
 	cat $^ | grep ^REGISTER_TEST > $@
 
-$(TEST_OBJS): tools/ccanlint/generated-normal-tests tools/ccanlint/generated-compulsory-tests
+$(TEST_OBJS): tools/ccanlint/generated-testlist
 
 # Otherwise, ccanlint.c et al. may fail to build
-$(CORE_OBJS): tools/ccanlint/generated-normal-tests tools/ccanlint/generated-compulsory-tests config.h
+$(CORE_OBJS): tools/ccanlint/generated-testlist config.h
 
 tools/ccanlint/ccanlint: $(OBJS)
 
 ccanlint-clean:
-	$(RM) tools/ccanlint/generated-compulsory-tests
-	$(RM) tools/ccanlint/generated-normal-tests
+	$(RM) tools/ccanlint/generated-testlist
 	$(RM) tools/ccanlint/ccanlint
-
diff --git a/tools/ccanlint/ccanlint.c b/tools/ccanlint/ccanlint.c
index 63724d2e..b35f11a7 100644
--- a/tools/ccanlint/ccanlint.c
+++ b/tools/ccanlint/ccanlint.c
@@ -33,10 +33,13 @@
 #include <ccan/foreach/foreach.h>
 #include <ccan/grab_file/grab_file.h>
 #include <ccan/cast/cast.h>
+#include <ccan/tlist/tlist.h>
+
+/* Defines struct tlist_ccanlint. */
+TLIST_TYPE(ccanlint, struct ccanlint);
 
 int verbose = 0;
-static struct list_head compulsory_tests;
-static struct list_head normal_tests;
+static struct tlist_ccanlint tests = TLIST_INIT(tests);
 bool safe_mode = false;
 static struct btree *cmdline_exclude;
 static struct btree *info_exclude;
@@ -182,9 +185,9 @@ static bool run_test(struct ccanlint *i,
 	return score->pass;
 }
 
-static void register_test(struct list_head *h, struct ccanlint *test)
+static void register_test(struct ccanlint *test)
 {
-	list_add(h, &test->list);
+	tlist_add(&tests, test, list);
 	test->options = talloc_array(NULL, char *, 1);
 	test->options[0] = NULL;
 	test->skip = NULL;
@@ -194,14 +197,14 @@ static void register_test(struct list_head *h, struct ccanlint *test)
 /**
  * get_next_test - retrieves the next test to be processed
  **/
-static inline struct ccanlint *get_next_test(struct list_head *test)
+static inline struct ccanlint *get_next_test(void)
 {
 	struct ccanlint *i;
 
-	if (list_empty(test))
+	if (tlist_empty(&tests))
 		return NULL;
 
-	list_for_each(test, i, list) {
+	tlist_for_each(&tests, i, list) {
 		if (i->num_depends == 0)
 			return i;
 	}
@@ -212,11 +215,7 @@ static struct ccanlint *find_test(const char *key)
 {
 	struct ccanlint *i;
 
-	list_for_each(&compulsory_tests, i, list)
-		if (streq(i->key, key))
-			return i;
-
-	list_for_each(&normal_tests, i, list)
+	tlist_for_each(&tests, i, list)
 		if (streq(i->key, key))
 			return i;
 
@@ -232,91 +231,74 @@ bool is_excluded(const char *name)
 
 #undef REGISTER_TEST
 #define REGISTER_TEST(name, ...) extern struct ccanlint name
-#include "generated-normal-tests"
-#include "generated-compulsory-tests"
+#include "generated-testlist"
 
 static void init_tests(void)
 {
 	struct ccanlint *c;
 	struct btree *keys, *names;
-	struct list_head *list;
 
-	list_head_init(&normal_tests);
-	list_head_init(&compulsory_tests);
+	tlist_init(&tests);
 
 #undef REGISTER_TEST
-#define REGISTER_TEST(name) register_test(&normal_tests, &name)
-#include "generated-normal-tests"
-#undef REGISTER_TEST
-#define REGISTER_TEST(name) register_test(&compulsory_tests, &name)
-#include "generated-compulsory-tests"
+#define REGISTER_TEST(name) register_test(&name)
+#include "generated-testlist"
 
 	/* Initialize dependency lists. */
-	foreach_ptr(list, &compulsory_tests, &normal_tests) {
-		list_for_each(list, c, list) {
-			list_head_init(&c->dependencies);
-			c->num_depends = 0;
-		}
+	tlist_for_each(&tests, c, list) {
+		list_head_init(&c->dependencies);
+		c->num_depends = 0;
 	}
 
 	/* Resolve dependencies. */
-	foreach_ptr(list, &compulsory_tests, &normal_tests) {
-		list_for_each(list, c, list) {
-			char **deps = strsplit(NULL, c->needs, " ");
-			unsigned int i;
-
-			for (i = 0; deps[i]; i++) {
-				struct ccanlint *dep;
-				struct dependent *dchild;
-
-				dep = find_test(deps[i]);
-				if (!dep)
-					errx(1, "BUG: unknown dep '%s' for %s",
-					     deps[i], c->key);
-				dchild = talloc(NULL, struct dependent);
-				dchild->dependent = c;
-				list_add_tail(&dep->dependencies,
-					      &dchild->node);
-				c->num_depends++;
-			}
-			talloc_free(deps);
+	tlist_for_each(&tests, c, list) {
+		char **deps = strsplit(NULL, c->needs, " ");
+		unsigned int i;
+
+		for (i = 0; deps[i]; i++) {
+			struct ccanlint *dep;
+			struct dependent *dchild;
+
+			dep = find_test(deps[i]);
+			if (!dep)
+				errx(1, "BUG: unknown dep '%s' for %s",
+				     deps[i], c->key);
+			dchild = talloc(NULL, struct dependent);
+			dchild->dependent = c;
+			list_add_tail(&dep->dependencies, &dchild->node);
+			c->num_depends++;
 		}
+		talloc_free(deps);
 	}
 
 	/* Self-consistency check: make sure no two tests
 	   have the same key or name. */
 	keys = btree_new(btree_strcmp);
 	names = btree_new(btree_strcmp);
-	foreach_ptr(list, &compulsory_tests, &normal_tests) {
-		list_for_each(list, c, list) {
-			if (!btree_insert(keys, c->key))
-				errx(1, "BUG: Duplicate test key '%s'",
-				     c->key);
-			if (!btree_insert(names, c->name))
-				errx(1, "BUG: Duplicate test name '%s'",
-				     c->name);
-		}
+	tlist_for_each(&tests, c, list) {
+		if (!btree_insert(keys, c->key))
+			errx(1, "BUG: Duplicate test key '%s'",
+			     c->key);
+		if (!btree_insert(names, c->name))
+			errx(1, "BUG: Duplicate test name '%s'",
+			     c->name);
 	}
+
 	btree_delete(keys);
 	btree_delete(names);
 }
 
 static void print_test_depends(void)
 {
-	struct list_head *list;
-
-	foreach_ptr(list, &compulsory_tests, &normal_tests) {
-		struct ccanlint *c;
-		printf("\%s Tests\n",
-		       list == &compulsory_tests ? "Compulsory" : "Normal");
-
-		list_for_each(list, c, list) {
-			if (!list_empty(&c->dependencies)) {
-				const struct dependent *d;
-				printf("These depend on %s:\n", c->key);
-				list_for_each(&c->dependencies, d, node)
-					printf("\t%s\n", d->dependent->key);
-			}
+	struct ccanlint *c;
+	printf("Tests:\n");
+
+	tlist_for_each(&tests, c, list) {
+		if (!list_empty(&c->dependencies)) {
+			const struct dependent *d;
+			printf("These depend on %s:\n", c->key);
+			list_for_each(&c->dependencies, d, node)
+				printf("\t%s\n", d->dependent->key);
 		}
 	}
 }
@@ -333,11 +315,8 @@ static char *keep_test(const char *testname, void *unused)
 
 	init_tests();
 	if (streq(testname, "all")) {
-		struct list_head *list;
-		foreach_ptr(list, &compulsory_tests, &normal_tests) {
-			list_for_each(list, i, list)
-				i->keep_results = true;
-		}
+		tlist_for_each(&tests, i, list)
+			i->keep_results = true;
 	} else {
 		i = find_test(testname);
 		if (!i)
@@ -356,34 +335,29 @@ static char *skip_test(const char *testname, void *unused)
 	return NULL;
 }
 
-static void print_tests(struct list_head *tests, const char *type)
+static char *list_tests(void *arg)
 {
 	struct ccanlint *i;
 
-	printf("%s tests:\n", type);
+	init_tests();
+
+	printf("Tests:\n");
 	/* This makes them print in topological order. */
-	while ((i = get_next_test(tests)) != NULL) {
+	while ((i = get_next_test()) != NULL) {
 		const struct dependent *d;
 		printf("   %-25s %s\n", i->key, i->name);
 		list_del(&i->list);
 		list_for_each(&i->dependencies, d, node)
 			d->dependent->num_depends--;
 	}
-}
-
-static char *list_tests(void *arg)
-{
-	init_tests();
-	print_tests(&compulsory_tests, "Compulsory");
-	print_tests(&normal_tests, "Normal");
 	exit(0);
 }
 
-static void test_dgraph_vertices(struct list_head *tests, const char *style)
+static void test_dgraph_vertices(const char *style)
 {
 	const struct ccanlint *i;
 
-	list_for_each(tests, i, list) {
+	tlist_for_each(&tests, i, list) {
 		/*
 		 * todo: escape labels in case ccanlint test keys have
 		 *       characters interpreted as GraphViz syntax.
@@ -392,12 +366,12 @@ static void test_dgraph_vertices(struct list_head *tests, const char *style)
 	}
 }
 
-static void test_dgraph_edges(struct list_head *tests)
+static void test_dgraph_edges(void)
 {
 	const struct ccanlint *i;
 	const struct dependent *d;
 
-	list_for_each(tests, i, list)
+	tlist_for_each(&tests, i, list)
 		list_for_each(&i->dependencies, d, node)
 			printf("\t\"%p\" -> \"%p\"\n", d->dependent, i);
 }
@@ -407,11 +381,8 @@ static char *test_dependency_graph(void *arg)
 	init_tests();
 	puts("digraph G {");
 
-	test_dgraph_vertices(&compulsory_tests, ", style=filled, fillcolor=yellow");
-	test_dgraph_vertices(&normal_tests,     "");
-
-	test_dgraph_edges(&compulsory_tests);
-	test_dgraph_edges(&normal_tests);
+	test_dgraph_vertices("");
+	test_dgraph_edges();
 
 	puts("}");
 
@@ -552,12 +523,10 @@ static bool depends_on(struct ccanlint *i, struct ccanlint *target)
 static void skip_unrelated_tests(struct ccanlint *target)
 {
 	struct ccanlint *i;
-	struct list_head *list;
 
-	foreach_ptr(list, &compulsory_tests, &normal_tests)
-		list_for_each(list, i, list)
-			if (!depends_on(i, target))
-				i->skip = "not relevant to target";
+	tlist_for_each(&tests, i, list)
+		if (!depends_on(i, target))
+			i->skip = "not relevant to target";
 }
 
 static char *demangle_string(char *string)
@@ -726,6 +695,8 @@ int main(int argc, char *argv[])
 
 	for (i = 1; i < argc; i++) {
 		unsigned int score, total_score;
+		bool added_info_options = false;
+
 		dir = argv[i];
 
 		if (dir[0] != '/')
@@ -762,26 +733,25 @@ int main(int argc, char *argv[])
 		if (symlink(talloc_asprintf(m, "%s/test", dir), testlink) != 0)
 			err(1, "Creating test symlink in %s", temp_dir(NULL));
 
-		/* If you don't pass the compulsory tests, score is 0. */
 		score = total_score = 0;
-		while ((t = get_next_test(&compulsory_tests)) != NULL) {
+		while ((t = get_next_test()) != NULL) {
 			if (!run_test(t, summary, &score, &total_score, m,
 				      prefix)) {
-				warnx("%s%s failed", prefix, t->name);
-				printf("%sTotal score: 0/%u\n",
-				       prefix, total_score);
 				pass = false;
-				goto next;
+				if (t->compulsory) {
+					warnx("%s%s failed", prefix, t->name);
+					printf("%sTotal score: 0/%u\n",
+					       prefix, total_score);
+					goto next;
+				}
 			}
-		}
 
-		/* --target overrides known FAIL from _info */
-		if (m->info_file)
-			add_info_options(m->info_file, !target);
-
-		while ((t = get_next_test(&normal_tests)) != NULL)
-			pass &= run_test(t, summary, &score, &total_score, m,
-					 prefix);
+			/* --target overrides known FAIL from _info */
+			if (!added_info_options && m->info_file) {
+				add_info_options(m->info_file, !target);
+				added_info_options = true;
+			}
+		}
 
 		printf("%sTotal score: %u/%u\n", prefix, score, total_score);
 	next: ;
diff --git a/tools/ccanlint/ccanlint.h b/tools/ccanlint/ccanlint.h
index 452b44f7..16600cff 100644
--- a/tools/ccanlint/ccanlint.h
+++ b/tools/ccanlint/ccanlint.h
@@ -91,6 +91,9 @@ struct ccanlint {
 	/* Can we run this test?  Return string explaining why, if not. */
 	const char *(*can_run)(struct manifest *m);
 
+	/* Should we stop immediately if test fails? */
+	bool compulsory;
+
 	/* keep is set if you should keep the results.
 	 * If timeleft is set to 0, means it timed out.
 	 * score is the result, and a talloc context freed after all our
diff --git a/tools/ccanlint/compulsory_tests/build.h b/tools/ccanlint/compulsory_tests/build.h
deleted file mode 100644
index 04140bf9..00000000
--- a/tools/ccanlint/compulsory_tests/build.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef CCANLINT_BUILD_H
-#define CCANLINT_BUILD_H
-char *build_module(struct manifest *m, bool keep, enum compile_type ctype,
-		   char **errstr);
-char *build_submodule(struct manifest *m, const char *flags,
-		      enum compile_type ctype);
-void build_objects(struct manifest *m,
-		   bool keep, struct score *score, const char *flags,
-		   enum compile_type ctype);
-#endif /* CCANLINT_BUILD_H */
diff --git a/tools/ccanlint/compulsory_tests/depends_exist.c b/tools/ccanlint/compulsory_tests/depends_exist.c
deleted file mode 100644
index b1694058..00000000
--- a/tools/ccanlint/compulsory_tests/depends_exist.c
+++ /dev/null
@@ -1,91 +0,0 @@
-#include <tools/ccanlint/ccanlint.h>
-#include <tools/tools.h>
-#include <ccan/talloc/talloc.h>
-#include <ccan/str/str.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <err.h>
-#include <string.h>
-#include <ctype.h>
-
-static bool add_dep(struct manifest *m, const char *dep, struct score *score)
-{
-	struct stat st;
-	struct manifest *subm;
-	char *dir = talloc_asprintf(m, "%s/%s", ccan_dir, dep);
-
-	/* FIXME: get_manifest has a tendency to exit. */
-	if (stat(dir, &st) != 0) {
-		score->error
-			= talloc_asprintf(m,
-					  "Could not stat dependency %s: %s",
-					  dir, strerror(errno));
-		return false;
-	}
-	subm = get_manifest(m, dir);
-	list_add_tail(&m->deps, &subm->list);
-	return true;
-}
-
-/* FIXME: check this is still true once we reduce features. */
-static void check_depends_exist(struct manifest *m,
-				bool keep,
-				unsigned int *timeleft, struct score *score)
-{
-	unsigned int i;
-	char **deps;
-	char *updir = talloc_strdup(m, m->dir);
-	bool needs_tap;
-
-	if (strrchr(updir, '/'))
-		*strrchr(updir, '/') = '\0';
-
-	/* We may need libtap for testing, unless we're "tap" */
-	if (streq(m->basename, "tap")) {
-		needs_tap = false;
-	} else if (list_empty(&m->run_tests) && list_empty(&m->api_tests)) {
-		needs_tap = false;
-	} else {
-		needs_tap = true;
-	}
-
-	if (safe_mode)
-		deps = get_safe_ccan_deps(m, m->dir, true);
-	else
-		deps = get_deps(m, m->dir, true,
-				&m->info_file->compiled[COMPILE_NORMAL]);
-
-	for (i = 0; deps[i]; i++) {
-		if (!strstarts(deps[i], "ccan/"))
-			continue;
-
-		if (!add_dep(m, deps[i], score))
-			return;
-
-		if (streq(deps[i], "ccan/tap")) {
-			needs_tap = false;
-		}
-	}
-
-	if (needs_tap && !add_dep(m, "ccan/tap", score)) {
-		return;
-	}
-
-	score->pass = true;
-	score->score = score->total;
-}
-
-struct ccanlint depends_exist = {
-	.key = "depends_exist",
-	.name = "Module's CCAN dependencies can be found",
-	.check = check_depends_exist,
-	.needs = "info_exists"
-};
-
-REGISTER_TEST(depends_exist);
diff --git a/tools/ccanlint/compulsory_tests/info_exists.c b/tools/ccanlint/compulsory_tests/info_exists.c
deleted file mode 100644
index ac840119..00000000
--- a/tools/ccanlint/compulsory_tests/info_exists.c
+++ /dev/null
@@ -1,86 +0,0 @@
-#include <tools/ccanlint/ccanlint.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <err.h>
-#include <string.h>
-#include <ccan/noerr/noerr.h>
-#include <ccan/talloc/talloc.h>
-
-static void check_has_info(struct manifest *m,
-			   bool keep,
-			   unsigned int *timeleft,
-			   struct score *score)
-{
-	if (m->info_file) {
-		score->pass = true;
-		score->score = score->total;
-	} else {
-		score->error = talloc_strdup(score,
-	"You have no _info file.\n\n"
-	"The file _info contains the metadata for a ccan package: things\n"
-	"like the dependencies, the documentation for the package as a whole\n"
-	"and license information.\n");
-	}
-}
-
-static const char template[] = 
-	"#include <string.h>\n"
-	"#include \"config.h\"\n"
-	"\n"
-	"/**\n"
-	" * %s - YOUR-ONE-LINE-DESCRIPTION-HERE\n"
-	" *\n"
-	" * This code ... YOUR-BRIEF-SUMMARY-HERE\n"
-	" *\n"
-	" * Example:\n"
-	" *	FULLY-COMPILABLE-INDENTED-TRIVIAL-BUT-USEFUL-EXAMPLE-HERE\n"
-	" */\n"
-	"int main(int argc, char *argv[])\n"
-	"{\n"
-	"	/* Expect exactly one argument */\n"
-	"	if (argc != 2)\n"
-	"		return 1;\n"
-	"\n"
-	"	if (strcmp(argv[1], \"depends\") == 0) {\n"
-	"		PRINTF-CCAN-PACKAGES-YOU-NEED-ONE-PER-LINE-IF-ANY\n"
-	"		return 0;\n"
-	"	}\n"
-	"\n"
-	"	return 1;\n"
-	"}\n";
-
-static void create_info_template(struct manifest *m, struct score *score)
-{
-	FILE *info;
-	const char *filename;
-
-	if (!ask("Should I create a template _info file for you?"))
-		return;
-
-	filename = talloc_asprintf(m, "%s/%s", m->dir, "_info");
-	info = fopen(filename, "w");
-	if (!info)
-		err(1, "Trying to create a template _info in %s", filename);
-
-	if (fprintf(info, template, m->basename) < 0) {
-		unlink_noerr(filename);
-		err(1, "Writing template into %s", filename);
-	}
-	fclose(info);
-}
-
-struct ccanlint info_exists = {
-	.key = "info_exists",
-	.name = "Module has _info file",
-	.check = check_has_info,
-	.handle = create_info_template,
-	.needs = ""
-};
-
-REGISTER_TEST(info_exists);
diff --git a/tools/ccanlint/compulsory_tests/module_builds.c b/tools/ccanlint/compulsory_tests/module_builds.c
deleted file mode 100644
index 23985d2c..00000000
--- a/tools/ccanlint/compulsory_tests/module_builds.c
+++ /dev/null
@@ -1,90 +0,0 @@
-#include <tools/ccanlint/ccanlint.h>
-#include <tools/tools.h>
-#include <ccan/talloc/talloc.h>
-#include <ccan/str/str.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <err.h>
-#include <string.h>
-#include <ctype.h>
-#include "build.h"
-
-static const char *can_build(struct manifest *m)
-{
-	if (safe_mode)
-		return "Safe mode enabled";
-	return NULL;
-}
-
-static char *obj_list(const struct manifest *m, enum compile_type ctype)
-{
-	char *list = talloc_strdup(m, "");
-	struct ccan_file *i;
-
-	/* Objects from all the C files. */
-	list_for_each(&m->c_files, i, list)
-		list = talloc_asprintf_append(list, "%s ",
-					      i->compiled[ctype]);
-
-	return list;
-}
-
-char *build_module(struct manifest *m, bool keep,
-		   enum compile_type ctype, char **errstr)
-{
-	char *name = link_objects(m, m->basename, false, obj_list(m, ctype),
-				  errstr);
-	if (name) {
-		if (keep) {
-			char *realname = talloc_asprintf(m, "%s.o", m->dir);
-			assert(ctype == COMPILE_NORMAL);
-			/* We leave this object file around, all built. */
-			if (!move_file(name, realname))
-				err(1, "Renaming %s to %s", name, realname);
-			name = realname;
-		}
-	}
-	return name;
-}
-
-static void do_build(struct manifest *m,
-		     bool keep,
-		     unsigned int *timeleft,
-		     struct score *score)
-{
-	char *errstr;
-
-	if (list_empty(&m->c_files)) {
-		/* No files?  No score, but we "pass". */
-		score->total = 0;
-		score->pass = true;
-		return;
-	}
-
-	m->compiled[COMPILE_NORMAL]
-		= build_module(m, keep, COMPILE_NORMAL, &errstr);
-	if (!m->compiled[COMPILE_NORMAL]) {
-		score_file_error(score, NULL, 0, "%s", errstr);
-		return;
-	}
-
-	score->pass = true;
-	score->score = score->total;
-}
-
-struct ccanlint module_builds = {
-	.key = "module_builds",
-	.name = "Module can be built from object files",
-	.check = do_build,
-	.can_run = can_build,
-	.needs = "objects_build"
-};
-
-REGISTER_TEST(module_builds);
-
diff --git a/tools/ccanlint/compulsory_tests/objects_build.c b/tools/ccanlint/compulsory_tests/objects_build.c
deleted file mode 100644
index 2132b173..00000000
--- a/tools/ccanlint/compulsory_tests/objects_build.c
+++ /dev/null
@@ -1,79 +0,0 @@
-#include <tools/ccanlint/ccanlint.h>
-#include <tools/tools.h>
-#include <ccan/talloc/talloc.h>
-#include <ccan/str/str.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <err.h>
-#include <string.h>
-#include <ctype.h>
-#include "build.h"
-
-static const char *can_build(struct manifest *m)
-{
-	if (safe_mode)
-		return "Safe mode enabled";
-	return NULL;
-}
-
-void build_objects(struct manifest *m,
-		   bool keep, struct score *score, const char *flags,
-		   enum compile_type ctype)
-{
-	struct ccan_file *i;
-	bool errors = false, warnings = false;
-
-	if (list_empty(&m->c_files))
-		score->total = 0;
-	else
-		score->total = 2;
-
-	list_for_each(&m->c_files, i, list) {
-		char *output;
-		char *fullfile = talloc_asprintf(m, "%s/%s", m->dir, i->name);
-
-		i->compiled[ctype] = maybe_temp_file(m, "", keep, fullfile);
-		if (!compile_object(score, fullfile, ccan_dir, compiler, flags,
-				    i->compiled[ctype], &output)) {
-			talloc_free(i->compiled[ctype]);
-			score_file_error(score, i, 0,
-					 "Compiling object files:\n%s",
-					 output);
-			errors = true;
-		} else if (!streq(output, "")) {
-			score_file_error(score, i, 0,
-					 "Compiling object files gave"
-					 " warnings:\n%s",
-					 output);
-			warnings = true;
-		}
-	}
-
-	if (!errors) {
-		score->pass = true;
-		score->score = score->total - warnings;
-	}
-}
-
-static void check_objs_build(struct manifest *m,
-			     bool keep,
-			     unsigned int *timeleft, struct score *score)
-{
-	build_objects(m, keep, score, cflags, COMPILE_NORMAL);
-}
-
-struct ccanlint objects_build = {
-	.key = "objects_build",
-	.name = "Module object files can be built",
-	.check = check_objs_build,
-	.can_run = can_build,
-	.needs = "depends_exist"
-};
-
-REGISTER_TEST(objects_build);
diff --git a/tools/ccanlint/tests/build.h b/tools/ccanlint/tests/build.h
new file mode 100644
index 00000000..04140bf9
--- /dev/null
+++ b/tools/ccanlint/tests/build.h
@@ -0,0 +1,10 @@
+#ifndef CCANLINT_BUILD_H
+#define CCANLINT_BUILD_H
+char *build_module(struct manifest *m, bool keep, enum compile_type ctype,
+		   char **errstr);
+char *build_submodule(struct manifest *m, const char *flags,
+		      enum compile_type ctype);
+void build_objects(struct manifest *m,
+		   bool keep, struct score *score, const char *flags,
+		   enum compile_type ctype);
+#endif /* CCANLINT_BUILD_H */
diff --git a/tools/ccanlint/tests/depends_build.c b/tools/ccanlint/tests/depends_build.c
index e7faa1f1..ea5c3926 100644
--- a/tools/ccanlint/tests/depends_build.c
+++ b/tools/ccanlint/tests/depends_build.c
@@ -13,7 +13,7 @@
 #include <err.h>
 #include <string.h>
 #include <ctype.h>
-#include "../compulsory_tests/build.h"
+#include "build.h"
 
 static const char *can_build(struct manifest *m)
 {
diff --git a/tools/ccanlint/tests/depends_build_without_features.c b/tools/ccanlint/tests/depends_build_without_features.c
index 9982d27b..dfa96d72 100644
--- a/tools/ccanlint/tests/depends_build_without_features.c
+++ b/tools/ccanlint/tests/depends_build_without_features.c
@@ -14,7 +14,7 @@
 #include <string.h>
 #include <ctype.h>
 #include "reduce_features.h"
-#include "../compulsory_tests/build.h"
+#include "build.h"
 
 static const char *can_build(struct manifest *m)
 {
@@ -55,7 +55,7 @@ struct ccanlint depends_build_without_features = {
 	.name = "Module's CCAN dependencies can be found or built (reduced features)",
 	.check = check_depends_built_without_features,
 	.can_run = can_build,
-	.needs = "depends_exist reduce_features"
+	.needs = "depends_build reduce_features"
 };
 
 REGISTER_TEST(depends_build_without_features);
diff --git a/tools/ccanlint/tests/depends_exist.c b/tools/ccanlint/tests/depends_exist.c
new file mode 100644
index 00000000..ff67857f
--- /dev/null
+++ b/tools/ccanlint/tests/depends_exist.c
@@ -0,0 +1,92 @@
+#include <tools/ccanlint/ccanlint.h>
+#include <tools/tools.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/str/str.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <string.h>
+#include <ctype.h>
+
+static bool add_dep(struct manifest *m, const char *dep, struct score *score)
+{
+	struct stat st;
+	struct manifest *subm;
+	char *dir = talloc_asprintf(m, "%s/%s", ccan_dir, dep);
+
+	/* FIXME: get_manifest has a tendency to exit. */
+	if (stat(dir, &st) != 0) {
+		score->error
+			= talloc_asprintf(m,
+					  "Could not stat dependency %s: %s",
+					  dir, strerror(errno));
+		return false;
+	}
+	subm = get_manifest(m, dir);
+	list_add_tail(&m->deps, &subm->list);
+	return true;
+}
+
+/* FIXME: check this is still true once we reduce features. */
+static void check_depends_exist(struct manifest *m,
+				bool keep,
+				unsigned int *timeleft, struct score *score)
+{
+	unsigned int i;
+	char **deps;
+	char *updir = talloc_strdup(m, m->dir);
+	bool needs_tap;
+
+	if (strrchr(updir, '/'))
+		*strrchr(updir, '/') = '\0';
+
+	/* We may need libtap for testing, unless we're "tap" */
+	if (streq(m->basename, "tap")) {
+		needs_tap = false;
+	} else if (list_empty(&m->run_tests) && list_empty(&m->api_tests)) {
+		needs_tap = false;
+	} else {
+		needs_tap = true;
+	}
+
+	if (safe_mode)
+		deps = get_safe_ccan_deps(m, m->dir, true);
+	else
+		deps = get_deps(m, m->dir, true,
+				&m->info_file->compiled[COMPILE_NORMAL]);
+
+	for (i = 0; deps[i]; i++) {
+		if (!strstarts(deps[i], "ccan/"))
+			continue;
+
+		if (!add_dep(m, deps[i], score))
+			return;
+
+		if (streq(deps[i], "ccan/tap")) {
+			needs_tap = false;
+		}
+	}
+
+	if (needs_tap && !add_dep(m, "ccan/tap", score)) {
+		return;
+	}
+
+	score->pass = true;
+	score->score = score->total;
+}
+
+struct ccanlint depends_exist = {
+	.key = "depends_exist",
+	.name = "Module's CCAN dependencies can be found",
+	.compulsory = true,
+	.check = check_depends_exist,
+	.needs = "info_exists"
+};
+
+REGISTER_TEST(depends_exist);
diff --git a/tools/ccanlint/tests/examples_compile.c b/tools/ccanlint/tests/examples_compile.c
index d52ee789..3cbb23fd 100644
--- a/tools/ccanlint/tests/examples_compile.c
+++ b/tools/ccanlint/tests/examples_compile.c
@@ -12,7 +12,7 @@
 #include <ctype.h>
 #include <assert.h>
 #include <err.h>
-#include "../compulsory_tests/build.h"
+#include "build.h"
 
 static const char *can_run(struct manifest *m)
 {
diff --git a/tools/ccanlint/tests/hash_if.c b/tools/ccanlint/tests/hash_if.c
index 35608ef1..9e10c304 100644
--- a/tools/ccanlint/tests/hash_if.c
+++ b/tools/ccanlint/tests/hash_if.c
@@ -71,7 +71,7 @@ struct ccanlint hash_if = {
 	.key = "hash_if",
 	.name = "Features are checked with #if not #ifdef",
 	.check = check_hash_if,
-	.needs = ""
+	.needs = "info_exists"
 };
 
 REGISTER_TEST(hash_if);
diff --git a/tools/ccanlint/tests/headers_idempotent.c b/tools/ccanlint/tests/headers_idempotent.c
index f23784e4..4b98b246 100644
--- a/tools/ccanlint/tests/headers_idempotent.c
+++ b/tools/ccanlint/tests/headers_idempotent.c
@@ -195,7 +195,7 @@ struct ccanlint headers_idempotent = {
 	.name = "Module headers are #ifndef/#define wrapped",
 	.check = check_idempotent,
 	.handle = handle_idem,
-	.needs = ""
+	.needs = "info_exists main_header_exists"
 };
 
 REGISTER_TEST(headers_idempotent);
diff --git a/tools/ccanlint/tests/info_exists.c b/tools/ccanlint/tests/info_exists.c
new file mode 100644
index 00000000..80edb5aa
--- /dev/null
+++ b/tools/ccanlint/tests/info_exists.c
@@ -0,0 +1,87 @@
+#include <tools/ccanlint/ccanlint.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <string.h>
+#include <ccan/noerr/noerr.h>
+#include <ccan/talloc/talloc.h>
+
+static void check_has_info(struct manifest *m,
+			   bool keep,
+			   unsigned int *timeleft,
+			   struct score *score)
+{
+	if (m->info_file) {
+		score->pass = true;
+		score->score = score->total;
+	} else {
+		score->error = talloc_strdup(score,
+	"You have no _info file.\n\n"
+	"The file _info contains the metadata for a ccan package: things\n"
+	"like the dependencies, the documentation for the package as a whole\n"
+	"and license information.\n");
+	}
+}
+
+static const char template[] =
+	"#include <string.h>\n"
+	"#include \"config.h\"\n"
+	"\n"
+	"/**\n"
+	" * %s - YOUR-ONE-LINE-DESCRIPTION-HERE\n"
+	" *\n"
+	" * This code ... YOUR-BRIEF-SUMMARY-HERE\n"
+	" *\n"
+	" * Example:\n"
+	" *	FULLY-COMPILABLE-INDENTED-TRIVIAL-BUT-USEFUL-EXAMPLE-HERE\n"
+	" */\n"
+	"int main(int argc, char *argv[])\n"
+	"{\n"
+	"	/* Expect exactly one argument */\n"
+	"	if (argc != 2)\n"
+	"		return 1;\n"
+	"\n"
+	"	if (strcmp(argv[1], \"depends\") == 0) {\n"
+	"		PRINTF-CCAN-PACKAGES-YOU-NEED-ONE-PER-LINE-IF-ANY\n"
+	"		return 0;\n"
+	"	}\n"
+	"\n"
+	"	return 1;\n"
+	"}\n";
+
+static void create_info_template(struct manifest *m, struct score *score)
+{
+	FILE *info;
+	const char *filename;
+
+	if (!ask("Should I create a template _info file for you?"))
+		return;
+
+	filename = talloc_asprintf(m, "%s/%s", m->dir, "_info");
+	info = fopen(filename, "w");
+	if (!info)
+		err(1, "Trying to create a template _info in %s", filename);
+
+	if (fprintf(info, template, m->basename) < 0) {
+		unlink_noerr(filename);
+		err(1, "Writing template into %s", filename);
+	}
+	fclose(info);
+}
+
+struct ccanlint info_exists = {
+	.key = "info_exists",
+	.name = "Module has _info file",
+	.compulsory = true,
+	.check = check_has_info,
+	.handle = create_info_template,
+	.needs = ""
+};
+
+REGISTER_TEST(info_exists);
diff --git a/tools/ccanlint/tests/module_builds.c b/tools/ccanlint/tests/module_builds.c
new file mode 100644
index 00000000..52059af7
--- /dev/null
+++ b/tools/ccanlint/tests/module_builds.c
@@ -0,0 +1,90 @@
+#include <tools/ccanlint/ccanlint.h>
+#include <tools/tools.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/str/str.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <string.h>
+#include <ctype.h>
+#include "build.h"
+
+static const char *can_build(struct manifest *m)
+{
+	if (safe_mode)
+		return "Safe mode enabled";
+	return NULL;
+}
+
+static char *obj_list(const struct manifest *m, enum compile_type ctype)
+{
+	char *list = talloc_strdup(m, "");
+	struct ccan_file *i;
+
+	/* Objects from all the C files. */
+	list_for_each(&m->c_files, i, list)
+		list = talloc_asprintf_append(list, "%s ",
+					      i->compiled[ctype]);
+
+	return list;
+}
+
+char *build_module(struct manifest *m, bool keep,
+		   enum compile_type ctype, char **errstr)
+{
+	char *name = link_objects(m, m->basename, false, obj_list(m, ctype),
+				  errstr);
+	if (name) {
+		if (keep) {
+			char *realname = talloc_asprintf(m, "%s.o", m->dir);
+			assert(ctype == COMPILE_NORMAL);
+			/* We leave this object file around, all built. */
+			if (!move_file(name, realname))
+				err(1, "Renaming %s to %s", name, realname);
+			name = realname;
+		}
+	}
+	return name;
+}
+
+static void do_build(struct manifest *m,
+		     bool keep,
+		     unsigned int *timeleft,
+		     struct score *score)
+{
+	char *errstr;
+
+	if (list_empty(&m->c_files)) {
+		/* No files?  No score, but we "pass". */
+		score->total = 0;
+		score->pass = true;
+		return;
+	}
+
+	m->compiled[COMPILE_NORMAL]
+		= build_module(m, keep, COMPILE_NORMAL, &errstr);
+	if (!m->compiled[COMPILE_NORMAL]) {
+		score_file_error(score, NULL, 0, "%s", errstr);
+		return;
+	}
+
+	score->pass = true;
+	score->score = score->total;
+}
+
+struct ccanlint module_builds = {
+	.key = "module_builds",
+	.name = "Module can be built from object files",
+	.compulsory = true,
+	.check = do_build,
+	.can_run = can_build,
+	.needs = "objects_build"
+};
+
+REGISTER_TEST(module_builds);
diff --git a/tools/ccanlint/tests/no_trailing_whitespace.c b/tools/ccanlint/tests/no_trailing_whitespace.c
index f046a248..5d3b5ca1 100644
--- a/tools/ccanlint/tests/no_trailing_whitespace.c
+++ b/tools/ccanlint/tests/no_trailing_whitespace.c
@@ -53,7 +53,7 @@ struct ccanlint no_trailing_whitespace = {
 	.key = "no_trailing_whitespace",
 	.name = "Module's source code has no trailing whitespace",
 	.check = check_trailing_whitespace,
-	.needs = ""
+	.needs = "info_exists"
 };
 
 
diff --git a/tools/ccanlint/tests/objects_build.c b/tools/ccanlint/tests/objects_build.c
new file mode 100644
index 00000000..8fc11266
--- /dev/null
+++ b/tools/ccanlint/tests/objects_build.c
@@ -0,0 +1,80 @@
+#include <tools/ccanlint/ccanlint.h>
+#include <tools/tools.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/str/str.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <err.h>
+#include <string.h>
+#include <ctype.h>
+#include "build.h"
+
+static const char *can_build(struct manifest *m)
+{
+	if (safe_mode)
+		return "Safe mode enabled";
+	return NULL;
+}
+
+void build_objects(struct manifest *m,
+		   bool keep, struct score *score, const char *flags,
+		   enum compile_type ctype)
+{
+	struct ccan_file *i;
+	bool errors = false, warnings = false;
+
+	if (list_empty(&m->c_files))
+		score->total = 0;
+	else
+		score->total = 2;
+
+	list_for_each(&m->c_files, i, list) {
+		char *output;
+		char *fullfile = talloc_asprintf(m, "%s/%s", m->dir, i->name);
+
+		i->compiled[ctype] = maybe_temp_file(m, "", keep, fullfile);
+		if (!compile_object(score, fullfile, ccan_dir, compiler, flags,
+				    i->compiled[ctype], &output)) {
+			talloc_free(i->compiled[ctype]);
+			score_file_error(score, i, 0,
+					 "Compiling object files:\n%s",
+					 output);
+			errors = true;
+		} else if (!streq(output, "")) {
+			score_file_error(score, i, 0,
+					 "Compiling object files gave"
+					 " warnings:\n%s",
+					 output);
+			warnings = true;
+		}
+	}
+
+	if (!errors) {
+		score->pass = true;
+		score->score = score->total - warnings;
+	}
+}
+
+static void check_objs_build(struct manifest *m,
+			     bool keep,
+			     unsigned int *timeleft, struct score *score)
+{
+	build_objects(m, keep, score, cflags, COMPILE_NORMAL);
+}
+
+struct ccanlint objects_build = {
+	.key = "objects_build",
+	.name = "Module object files can be built",
+	.compulsory = true,
+	.check = check_objs_build,
+	.can_run = can_build,
+	.needs = "depends_exist"
+};
+
+REGISTER_TEST(objects_build);
diff --git a/tools/ccanlint/tests/objects_build_without_features.c b/tools/ccanlint/tests/objects_build_without_features.c
index 477d3025..770dd475 100644
--- a/tools/ccanlint/tests/objects_build_without_features.c
+++ b/tools/ccanlint/tests/objects_build_without_features.c
@@ -1,7 +1,7 @@
 #include <tools/ccanlint/ccanlint.h>
 #include <ccan/talloc/talloc.h>
 #include "reduce_features.h"
-#include "../compulsory_tests/build.h"
+#include "build.h"
 
 static void check_objs_build_without_features(struct manifest *m,
 					      bool keep,
diff --git a/tools/ccanlint/tests/tests_compile.c b/tools/ccanlint/tests/tests_compile.c
index bfa412a6..ee1a6b2c 100644
--- a/tools/ccanlint/tests/tests_compile.c
+++ b/tools/ccanlint/tests/tests_compile.c
@@ -221,6 +221,6 @@ struct ccanlint tests_compile_without_features = {
 	.name = "Module tests compile (without features)",
 	.check = do_compile_tests_without_features,
 	.can_run = features_reduced,
-	.needs = "tests_helpers_compile_without_features objects_build_without_features"
+	.needs = "module_builds tests_helpers_compile_without_features objects_build_without_features"
 };
 REGISTER_TEST(tests_compile_without_features);
diff --git a/tools/ccanlint/tests/tests_compile_coverage.c b/tools/ccanlint/tests/tests_compile_coverage.c
index a1028110..accb9ffd 100644
--- a/tools/ccanlint/tests/tests_compile_coverage.c
+++ b/tools/ccanlint/tests/tests_compile_coverage.c
@@ -14,7 +14,7 @@
 #include <err.h>
 #include <string.h>
 #include <ctype.h>
-#include "../compulsory_tests/build.h"
+#include "build.h"
 #include "tests_compile.h"
 
 /* Note: we already test safe_mode in run_tests.c */
diff --git a/tools/ccanlint/tests/tests_exist.c b/tools/ccanlint/tests/tests_exist.c
index 523fe99f..57fd4e11 100644
--- a/tools/ccanlint/tests/tests_exist.c
+++ b/tools/ccanlint/tests/tests_exist.c
@@ -132,6 +132,6 @@ struct ccanlint tests_exist = {
 	.key = "tests_exist",
 	.name = "Module has test directory with tests in it",
 	.check = check_tests_exist,
-	.needs = ""
+	.needs = "info_exists"
 };